dixon



Feb. 13, 1923.

. Re. 15,539 T. B. DIXON TELEGRA PHY Original Filed May 11, 1920 5 sheets-sheet 1 Feb. 13, 1923. Re. 15,539 T. B. DIXON TELEGRJAPPIY" Original Filed Ma l -1 1%520 5 sheets'-sheet 2 HEY AT'T 1v 5; i

Feb. 13, 1923.

T. B. DIXON TELEGRAPHY sheets-sheet 5 Original Filed May 11 A R/VEYS.

Feb. 13, 1923.

T. B. pfxohj TELEGRA PHY Original Filed May ll, 1920 5 sheets-sheet 4f Feb. 13, 1923. Re; 15,539 'r. B. DIXON.

TELEGRAPH! Original Filed May 11, 1920 5 sheets-shet 5 m1} INVENTOR.

3W. v AT RNEYS.

6 Queens and State specification.

1 0 and-apparatus, and particular I and apparatus adapted for use HIQGOHHGCUOII' Rciulied Feb. is, #19 3.

"mm-r 0 seen; some mx'ox, or m You. x. I.

on uuu Io. 1,9, dated In! 11,

My invention relates telegra ii sysltzems y rays ems withylinesof .very reattretardation, such as submarine cables. n the method of transmitting; and receiving telegraphic signals,

most'commonly used on long submarine cable 35 with a piensiphon tube which tracesa wavy 9 imaginar of .transmission rises, the signals become in a 3 distinct, 'until, at what would be. a very.

lines dots and dashes ofthe telegraphic code are repre'sented' by current pulses of different directions, but of approximately'the' same duration, a positive pulse for example, indicatingdot, and ,a negative pulse, a dash. Thesiignals are received by an nstrument terme yafsiphon. recorder which is.

in its nature at very .sensitive galvanorneter the nloving member of which i is provided (thispenl line on a e'znovingv record. strip, waves tonne side of an imaginary-center pn' such strip deslgnatmg dots and--wavee totheother side of such low spec thesignals thus transmitted and 'received come out ,clearly', -but as the speed moderate speed for transmimion ovens land line, ,the -signalsrbecolnegso indistinct as the length of-the light beam'may be-va'ried'* i as desired or required, thereby efiecti-ng be: unintelligible.

resentfnvention comprisS 0 ampliging telegraphic signals, particularly] I sired range, without increas ng the inertia signals transmitted as described through circuits-01f, great retardation, whereby dis tinctsignalsare produced at speeds of transmission at which signals, if received in the ordinary way, would be unintelligible; and by the means for amplifying signals, herein described, Ihave been able to reach a speed o f transmission very much greater than any practicable speed oftransmission heretofore si'hle over the same or. corresponding mes.

My invention also consists in a *methodof amplifying telegra )hic signals transmitted through circuits 0 great .retardatiomsimh method comprisingcausing. the'current wave in such'circuit to vary: the'ac'tion of radiant mission being, in practice, a

center designating dashes. At I I V energy to act var ably on lldlOQlGGtl'O-Nllfli .,i

tive means (customarily oneor more l ni darkness. -In darkness selenium has very' high electric resistance, but wheri "brighflymmo, mm n. sou-rs, al a December 5,1518 Indication r i reissue filed Kay 8, 1981-. krill 10'. In)", i

energy on radio-electro-sensitivemeans, and causing such radiofelectrosensitive means to produce variations in current flow in -a-circuit comprisin signal-receiving means.

Thus, m -invention comprises, as; an appara: 00 his, signal-amplifying means comprisin -m:

diant-energy-varying means 'ada tedj'to be circuitandadapted to vary theac tion of radiant energy on radio-electro-sensi{ means in a circuit influenced electro-sensitivemeans.

As above stated, the receiving instrument'- commonly usedis in its nature a galvanomer for amplification of s" efiect of inertla nals as to defeat the desired Accord-1 mg to my present invention, substitutes reflector, or other '-means' 'for directing and M deflecting a beam of radiant ener a light beam),

(usually the recorder, and cause this beam of radiant 7a mechanical meansguformechanical means influenced by the currentwaves'o the tr ms-p.

:05 -tive means, together with signal r'gceiving 1' 8" qn 'e- J0 teriwhich constitutes the primary yreceifin'g als necessarily in-f volyesmovmg parts whichhave? inertiagthe" being-to s0 dampen the 'si for the-pen or sip on=tubeiof I efiectapointer of any desiredle' h,but

which'is entirely without inertia. erefore' movement of'the pointerthroughfanyf'de 1' of the movable galvanometer member; I

I- As is well known, selenium" is'a substance Y 7 vanes the electrical resistanw of whic reatly according as itbc in lig t or illuminated the resistance of the selenium" falls very greatly. similar properties.

and arelatively high resistance: when bright 1y illuminated. And my radio electro-sensi-- Other substances have Actinium for examplehas a relatively low resistance in darkness tive element-1s notnecessarily either-a sele= niurncell or an actinium cell; for a thermal couple such as 15 commonly-contained iua 1 'co I of such :thennopile'jwill nerate current variably if upon varia il by heat rays. Ipre'fer, however, to ii'se se eniur'n cells as the radioelectro sensitive elements employed according to" my invention, as in practice'I have found them very gene or m re f of light,variably deflected by the galvahqmeter reflector,

reliable, and I so locate these cells that the beam as previously described,

ml! move across: he face or faces of such sources of electric energy,for example, a

, and the variation of resistance of-the selenium cell 'or cells, due a thevariablerillumination of such cell or cells,

1 cellar-themselves in the .3

- I self.

variation in current. fiflch'circuit orcircuits, capable of, actuating element of a galvanometcr or ordinaryv siphon recorder; the amplification ofithe signals" of; the cable circuit, due to thc arilblc' deflection'of a beam of light by a rface' ;or'surfaces .of-"a selenium cell or I circuit of the siphon beings'o' great that intelligible and signals are produced speeds if the siphon er' were fl in the cable circuit'\itnot found that; of the 'ca'ble', ob ectionable 'pecularities are impressed upon such signals byIthe amplifymg apparatusw To the thanfthey would be if devices, together with senses" simultaneously upon has contrary, the signals remain of. the samecharacter as before, except that their quality. is improved, but the deflections of the plum recorder are I that siphon recorder wereidirectly in. the cable circuit, that intelligible and very clear signals are produced at speeds of transmission far above what been practicable I heretofore on similar circuits; l

1 Myinventionalso comprises a pair er I selenium cells orpther radio-electro-sensitive lurality of pairs of cells'or for. varying devices, or a p means energy in opposite the two cells'of the action of radiant such. pair or I with signal receiving means, and circuit means as hereinafter described, whereby as the action of -radiant energy is decreased upo e cellofi such a pair and is correspondingly-increased upon the other cell pair, the two. cells cooperate to produce cumulative or additive effect on such signal receiving device.

. object of my invention is the speed'and certainty to increase of transmisslon of connect such cell or cells to an or circuits conta ning a source reflector, actuated by such signals, over the I I I the speeds at which intelligible signals. would be produced I I the linegalvanometer to' former practice. If; halve by so amplifying the signal's stone bridge'of Fig. 4.

mova.ble member of they so very much greater line galvanometer'.

signals through electric circuits, particularly circuits of high retardation.

he accompanying drawings illustrate diagrammatically of telegraph signals, herein described. In said drawings: I j Figure 1 shows diagrammatically .an arrange-ment of transmitting, signal-amplifyand signal repeating mg, signal-receiving .means embodying my invention.

Figure 1 is a'detail diagram showing the tramsmitting circuits of'repeating relays 27 and 28 of Fig. 1. I

I Figure 2 is a diagram illustrating the use of one radio-electro-sensitive element inlie'u of the two radi0-electro-sensitive elements employed in Fig. 1 andfurther illustrates the fact that in the arrangement shown in ig. 1 each radio-elcctro-sensitive element 14 acts, "in a measure, independentmf the other,

Figure 3 shows an alternative arrangenient of circuits for use when a of radio-electro-sensitive elements. are employed, such elements being located in a Vheatstone bridge. "Figure 4 is a diagramsomewhat similar to Fig. 3, but indicating connections which may be employed when four radio-electrw siziisitive elements are employed in a VVheat' ne bridge circuit; Fig. 4 also illustrating the light beam and means for producing it,

and the coil and magnets of the receiving siphon recorder.

Figure 5 is a diagram illustrating, in conventional W heatstone bridge arrangement, the location of the several radio-electro-sensitiveelements in the arms of the lVheatgram illustrating means for repeating the amplified signals into another circuit.

Figure .7 is a Figure 6 is die and illustrating the use of a curbing cir: cult andcurbing windings on the coil of the Figure 8 is a diagram, similar to Fig. 4,

illustra'ting another arrangement whereby four radio-electro-sensitive elements may be employed in cooperative relation. a

Figure 9 is'a 'fraginentar perspective elevation of Fig. 6, and Fig. 10 shows a detail front elevation and partial Section of'the principal portions of the said receiving relay.

Figure 11. is a diagram illustrating af'urther alternative repeating arrangement.

Figure 12 sl 1ows, more or -less diagrami 125 contacts which maybe employed, and is part cularly adapted for use in a repeatingmat'ically, an alternative arrangement of instrument such as illustrated in Figs. 9 and 10, and illustrated Figs. 6, 7 and 11.

the means for amplification plurality I similar diagram ilIuStrat- "lIlg an alternative repeating arrangement,

the repeating re ay illustrated in Y i diagrammatically in Referring first to Fig. 1 numerals 1 and 1', designate two telegraphic keys (shown in this case, as keys designated to heoperated I by" hand) which operate corresponding transmitting relays 2, 2 by closing and breaking branch circuits of battery 3. The

"key 1, when depressed, will. close circuit a polarity ofpositive to earth and n from thisbattery to the relay 2, and the key 1,jwhen depressed, will close circuit to the relay 2; .'l he operation of either of these relays places. a transmitting battery 4 in 'CllClllt to send current into the cable 5,

which cable, as shown, connected for working in one direction, is provided with the usual block condensers 5 at. its two ends. Thecurrents sent into the cable will have a polarity of positive to line and'ne tire,

to earth when the relay 2 is opera and tive to linewhemthelcft hand relay 2 IS a erated.. At the receiving end of the cable there, is; a galvanometer comprising a soar pended coil '6, located in a magnetic field,

and in a circuit extendingqfrom the cable,

through'the'corresponding condenser to ground The rece ving galvanometer fur ""therccomprises a-nnrror 7 suspended b suspension fibers 9 to swing freely, an provided at its lower end end witha Tshaped piece}; connected to coil 6 by two delicate bers. 10; the points of connection of these fibersIO to the piece Sbeing, preferably,

closer together than the points of connection of said fibers to the coil 6, so that for any given angular movement of the coil 6,

the angular movement of the mirror 7 "is f'greater. Adsuitablesourceof light, 11, is

provided (the particular source diagram matically indicated being the carbons of an hereinafter mentioned. The

from the source 11 shapedby condensing.

electric arc lamp)' and the light beam from such beam of light lenses '12 and the screen 13 sothat its cross Isection, at the point where it strikes the selenium 'cells 14, would be approximately quareabut for the fact that it passes through .l. plane-cylindrical lens 15 which condenses it in one direction (1. e.,' condenses it verticaily with the lens 15 positioned as shown in" the drawing.) The beam; of light is therefore approximately rectangular where it [strikes upon the. 'selenium cells. The

selenium cells 14 have their mm'inals mnected with batteries 16land'l7 in '"cir'cnit branches 18 of a circuit 19 connectcd to the coil 20" of a siphon recorder 20; which recorder is itself a specific form of galvanometer. VYhen the" lightbeam is in central Jposition 'with respect to the two selenium cells, asindicated in the drawing. then. suining the ::1tt\ wl6 and 17 to be equal,

and-the res; tench, in the circuit branches recorders,

sourc'e passes through suitable lenses i 3 12 iind 'a screen 13 to the reflectorpi, and,

'ence is reflected variably -'to-selenium =cells hated, the two batteries 16 and" 1 oppose each other in the circuit 19'and no current will v110w through the coil 20' of the siphon I recorden When, however, the light 1 am is deflected from its central or zero position, indicated, to oneside or the other (for example, when the light beam is deflected from left to right, *suchdeflection corre spending it may be assumed, to a dot signal transmitted through the cable 15) current from battery 17 will redominate and flow h circuit 19 an coil 20' of the siphon reco er, thus causing movement of" the deflect on corresponding toa dash signal) the current of battery 16 will predominate.

I have" indicated that, as is usual of moving tape 22, moved forward continua" ously coil 20of.the side or the other. I .o y t My signal amplifyingdevi'ce mayalao be y,suitable feeding means .23, The siphon tube therefore traces a line along sip hon,tube or pen 21. 1: the deflection of 7 the li ht bear'n is'from right toleft (such sis .o in siph n j the siphon tube trails over-a strip -9Q the tape 22 as the-latterl novegwhich line I is deflected to one side or the other. when, the

recorder is deflected to zone 0 5 f used as a repeater; to this end the coil 20f mayoperate acontactidpoint '24 (shown in" the drawing as moon 21 itself) which contlict point24 plays tween contact stops 25 and 20 in circuit,re-:

on the siphon tube spectively, with repeating relays 27 'and 28 Y m circuit with a battery 29,;ohe side ofthis battery being c onnected by a conductor 30 to contact po1nt'24, and; the other side of-J 31, andfthroughrepeating' lay27, to con;

this battery being connected by dmducmi tact stop 25, and being also connected'bya conductor 32, through repeatingirelay 28, to

contact stop 26.'

When, the coil 6 of the receivin galvanometer is in central" position, aniithere fore, when the light beam playing upon the selenium cells is in zero position,

one half of each of the selenium cells 14 is illunii-j nated, the other half ofeach such cell being unilluminated. The resistances. of the two selenium cells should then be equal; but since 7 it is difficult to obtain two selenium cells of exactly the same resistance, I have'indicated in the drawing adjusting variable resistthe two circuit branches18 may equal."

The operation of the system is as followsz Supposing the transmitting key 1 to be depressed, then the negative pole of battery 4 is connected to the cable through'th'e co n *tacts of the relay, 2', and the positivepole;

of battery 4 is connected to ground through" v the contacts of the relay 2; and a current I123 ances 33 f'and 34, whereby the resistance or f be made. I

bridge arrangement wherein the two sele- Wave is transmitted through the cable 5, causing deflection of coil 6 of the receiving galvanom ete rland itmay be assumed that such deflection is to the right), which in turn causesthe beam of lightplaying on the selenium cells 14 to'move to the right, de-

creasing'the illumination of the left hand cell 14 and increasing theillumination of the righthand cell 14, and so increasing the resist'anc in the circuit branch 18 containing battery 16,,and decreasing the resistance in the circuit branch 18 containing battery 17,

thereby disturbing the balance theretofore existing between these two branch circuits and causing'flow of current through circuit 19which, in turn, causes deflection of coil 20', ,moving the tracing end of siphon tube ,21 (and it maybe assumed that such motion is to the right-). Similarly, depression of keysl will cause movement of the siphon tube 21 to the left.

While thetwo selenium cells 14, in the arrangement just described, cooperate to produce, by their. varying resistance, deflections of coil 20, they also operate independently in a sense; as is indicated by Fig. 2,

iwherein only one of these cells 14 is shown,-

5 the other cell 14" being 'replaced, by a halancing resistance 14; circuit arrangements being otherwise similar, the beam of light being indicated by a dotted rectangle 11.

It will be seen that while, with the beam of light in the position shown, and the resistance 14* adjusted to exactly balance the resistanceot the selenium cell 14 so illuminated, the batteries 16 and 17 neutralize each other respectively in the circuit 18, yet if that beam of light be moved, the consequently varied resistanceof cell 14 will cause a. current from the one battery or the other to pass through circuit 18 and deflect the coil 20.

Various arrangements of circuits includingthe selenium cells andthe coil 20 may be used. In Fig. 3, I indicate a Wheatstone nium cells 14 are each in one arm of the bridge, the coil 20- being in the cross wire 35 of the bridge, the latter being designated generally by the numberBG Instead of employing one cell only, or two cells only, a'larger number of selenium cells may be employed. In Fig. 4 I show one means for employing four selenium cells designated respectively by reference characters 14, 14", 14 and 14. The circuits are those of a Wheatstone bridge 86, as will be more apparent-from Fig. 5, wherein the circuits are shown in conventional Wheatstone ifi 'bridge arrangement, without regard tofthe relative physical positions of the various selenium cells; the coitQG being in the cross wire 35 of the bridge. The. principle ofthe I Wheatstone bridge being well known, it will 6 54b apparent that if movementof the beam of light 11* increases the illumination of selenium cells 14 and 14 and decreases the illumination of cells 14 and 14, there will i be a flow of current in one direction through the cross wire 35 of the bridge, producing a deflection of coil 20*; while if the change in illumination of the selenium cells be in the oppositesense, there will be a flow of current through the cross wire 35 in the opposite direction.

In the alternative arrangement shown in Fig. 8, the screen which shapes the light beam, which screen is in thisffigure designated by numeral 13*,is provided with-two apertures, dividing the light beam into two separate beams bothof which are directed upon and are reflected by the same mirror 7, and passing through the plano-cylindrical has a relatively small amplitude of movement.

I have found that the sharpness of definition ofthe signals, and the permissible speed of transmission, are greatly increased by the provision, in connection with the coil-6 of the receiving galvanometer, and also in con nection with the coil 20 of the siphon recorder, of a magnetic shunt 37, (see Fig. 1) i. e., a. resistance of high inductive value such as is commonly used in connection with siphon recorders in cable Systems; such shunted inductive resistances having,'as is well known, the effect of squaring the signals. And sometimes, as indicated particu- 'larly in Fig. 11, I employ, in connection with one or another of these magnetic shunts,

.a shunted condenser 38. By proper adjust ment of resistance and inductance of the magnetic shunt or shunts 37, and by proper adjustment of the reactance of the shunted condenser 38, I can so time or tune the circuits as to produce conditions most desirable for nals. v

In Figure 6 I illustrate a repeating arthe reception of telegraphic sigrangement which preferable to that indicated in Fig. 1, and in Figs. 9. and 10 I illustrate the mechanical construction ofthe repeating instrument indicated diagrammaticallyin Fig. 6. In Fig. 6, as before, numeral 7 designates the reflector operated by coil 6 (I do not show in Fig. 6, the source of the light beam reflected by this reflector 7) and "hu iiieials 14 'indicate the selenium and me-a1 aodesi "This 'coil, which is mounted to swing freely,

carriesanarr'n 40 provided with insulation "piecesfll and 41 adapted ,to engage and actuate mechanically, contact pieces 42 and' 42". carried by freely swinging contact arms "43 and 43'; and beneath these arms 43 and i, mounted to swing freely, and each provided 43' are other contact arms 44 and A4, also with a' contact screw 45 or 45 and with an 'xjiiisulation stop 46 or 46. As shown particularly inFi'gs. 9 and 10, the contact arms i 43 and 43 are carried b edsha'fts 47.having jewe bearings 48 which delicately mountjewel bearings serveto insulate the contact arms43 and 43" from the supports of such "bearings, the weight. of such shafts 47 and .thef'arms 43 lcarridthereb being carriedby jew'elstep bearings 49. p

44 and 44' are carried by similar shafts 47',

he contact'arms for'which shafts 47 however, jewel bearings are not provided, customarily, as insulation ofthe'se arms Y44 and 44 from their supports is 'not' re'quired,.and some slight'frictlonal.

retardation tomoti'on ,of thesearms 44 and 44" is'desired, such retarda on being supso 'plied, not. only b springs- 50. A support 51' is provided the slight friction of shifts 47" in their arings, but also by fricwith insulation stops 52, which serve to limit fthe rnotion of contact'arm s 44 and 44."-

' toward the center. Current is supplied to contact arms 43 and 43 through very flexible conductors 53, and current is similarly I supplied to contact arms 44 and 44 by very Contact arms43 and 43 are provided with light tension; springs 5,5 and 55" respectively, tending to hold the contact piece, 42 or 42,

ofltha'tarm, 43 or 43 against the insulation piece 41 or41f ofthe' arm 40.

ch f h t ct mechanisms 43-44 'etc.,"and'43i-44, aseparate battery, '56 or 56', is pmvided current passing from this battery through conductor 57 m- 5i? to arm- 43 or 43' and c'urrent passing from the other I ;side of the said batteryjhrough the magnet p and 160'.

of 'a'tran'siliitting relay 58 or 58 and thence through, a" eon'ductor 59' to contactarnr 44' or 44?,

Tdreduce'sparking at the contact points of, jc-ontact mechanisms 43 -44 and Bi -44",; Ijxprovidesluinted condehsers 60 The operation'of this instrument is as foll lows:

. f Supposing a current )ulse in the cable cir; cuit 5 to deflect th'elcoi 6 to one side or the 60 sele-ni'u'ln cells I4.' the coil 20 will 'be de- 'flected' 'to'hnesiilia "oi-tho other; according" other, so changing the villumim tion of the to the direction of such current pulse in cable circuit \Ve will assume that the coil 20' is moved to the left in Fig. (3. Such atesithe' coil of the gal fvinometer-contro ed by the selenium cells.

moves with contact arm;

into another circuit 5. 4

' with a siphon tu a moving tape 22, in order that the signals movement of .move the contact arm 48 {to the left, the contact piece 42 of the arm 43 immediately making contact with coritact piece 45 ofigarm 44, and so closing circuit through theinagnet ofrepeating relay 58.: .Thecontact 'arm 44, being mounted 'to move quite :fi'eely,

.15 @611 can. tact Places 42 and 455-hfliemade contact, so

that'the making of such. contact does not the right 0 of the contact mechanism-' 48'--44*.;"irithe sume'manner, and the oprafien' oftr'ans mitting relay 158" in :the same "manner. i

' It is convenien to rovide the :coil 20' "21' a apted to write upon received may belecordedand thatthere may bea check upon the signals transmitted by relaysx58and 58'. And for a. further check upon the signals transmitted by rela s 58 and 58 a further recorder. 61' ofsuitable type may be provided. J

In Fig. 7 I'show an arrangement of cir- ('uits'and instruments similar to that of Fig.

7 6, exceptthat one battery 62, is provided for Similarly; the movement'of the to Fig.4! will cause 'theoperation the two contact mechanisms 43-44 and 43 44" instead of a separate batteryi-for each such contact mechanism, and except that circuits are provided whereby the change of illumination of selenium cells '14, due to a deflection of mirror ,7, acts upon coil 6, first to assist the movement of such coil .alid-ren- %r it more prompt in its movement and then to curb the movement of such coil. To this end, the coilfi is provided with a supple-. mental. windin 63 in atcircuit 64 arranged to be reversei by pole changing contact mechanism 65 and 65 with which relays 58 and 58 are provided. Supposing coil 6 to be deflected and to vary the illuminationof selenium cells 14,'and thereby to cause defiection of coil 20", current passes through circuit-()4 (connected in parallel, as shown, to the circuit which operates coil 20") through the supplemental winding-63 of coil 6, in'u 'direction to enhance the motion of such coil 6, thereby, making themoti'on' of coil (3 more prompt and rapid but asv soon as one of the relays 58 orwIS. has been'operated, through the operation of coil 20, the current through such supplemental winding 63 is reversed, whereby tie deflectiall perfect in form and entirely readable. .Sti h' her speed of transmission has been -j: by me over this cable, whom-owing temporary conditions, the retardation '6 was lower than as given'above.

What I claim is:

"ing telegraphic signals comprising in com bination tworadio-electro-sensrtive ele- '10 ments, circuits including the same includin electric generators, a third circuit to w-hic the-circuits of said radio-electro-sen'sitive elements are connected,- the polarity of said electric generators being opposite with respect to such third circuit, an actuating element arranged to direct a beam of radiant 'ener upon both said radio-electro-sensitive e ements, and by its operation to vary the illuminatlo'n of such radio-electro-sensi-- tiveelementsin opposite senses respectively,

, 7 electro-sensitive hid beam normally illuminating substantialportions of both said radio-electro-sensitive elements, and a controlled element controlled by the said third circuit; 2

ing telegraphic signals comprising two radio- 0 ements, circuits 'includlng the same, electric generators in said circuits a third circuit tOlWlllch the circuits of sai radio-electro-sensitiveelements are connected, the polarities of said generators being opposite with respect to said third c1rcu1t,an actuating element arranged to deflect vari- 'a bly a beam of radiant energy across the surfaces of such radio-electro-sensitive elements, the said beam when in mid-position c'overin a considerable ortion of both said \radioae ectro-sensitive e ements, and a com ,lled element controlled by the said third 4 circuit.

1:3. Apparatus for receiving and amplifing telegraphic signals comprising two r qlectm-sensitive elements,- a separate circuit for each such element, a third circuit to which the circuits of said radio-electro sensitis e elements are connected in 0 position,

a galvanornete'r comprising a re ectorari: ranged to deflect aheam of radiant energy =variably across said radio-electro-sensitive elements, such beam' when in mid-position covering a considerable rtion of both said I radio-elcctro-sensitive e ements, and a controlled element controlled by said third circuit.

-4. Apparatus for receiving and amplifying telegraphic signals comprising two radio-eIedam-sensitivc elements, a separate circuit such element, a third circuit tcfwhich'ilncircuits of said radio-electrosensitive elements are connected-in opposifoam, a galvonometcr comprising-a reflector arran d to deflect a beam of radiant energy 7 vnriuilyacross said rudio-electro-sensitive elements, such beam when in mid-position 1. Apparatus for receiving and amplify Hector corresponding ,to a condition:of par- 2. 'Apparatus for receiving and amplify- 'ment of said conductor and arranged to re-. 2 'flect variably a beam ,of rad ant energy across the surface of ,such radlo-electro-sensitive element, the rest position ofsuch" retial illumination of said-radio-clcctro-sensie tive. element, a'controlled element. controlled b the circuit of said r dio-electro-sensitive e ement, said controlle element comprising curbing windings, and ;a curbing circuit connected to such windings and 'controllin means for such circuit controlled by sucr controlled clement. i 1 6. In telegraph a selenium relay comprising associnted selenium cells arranged to fortn two arms of a WVheatstone bridge .with suitable resistances in the other arms to balance the bridge, a'source' of current connected across one diagonal of the bridge, and a receiving'instrument and anin'ductive resistance inshunt one to the' other connected across the other diagonal of the bridge.

7. In tclegraphy, a selenium relay having an inductive shunt around the receiving in--100 strument adjusted to compensate for the-inertia of the selenium, A ,v a 8. ln telegraphy, u radio-electric relay comprising associated radio-electro-sensitivc 7 cells arranged to form two arms of a \Vheat stone bridgewithsuituble resistances in the I other arms to balance-the bridge, a source of current connected across one'diagonalof the bridge, and a receiving instrument and an inductive resistance in shunt one to the other connected across the other diagonal of the bridge. v I

9. Apparatus for receiving and amplifying telegraphic signals comprising in com-\ binution two associated 1'adio-clectr0sensitive elements. ,a controlled device, a main circuit including that controlled device, 'tw'o branch circuits connected 1;" said main circuit, one such branch circuid-containing one such rad!o-electro-sensitive element,

the other branch circuit containing the other radioelectro-sensitive element and batteries included one in one branch circuit and the other in the other branch circuit. the said batteries an'arranged that the ntial of the one battery opposes the potentiallof the other batteryas-m said main circuit, and signal controlled means. responsive to a telesoi -sensitive elements in the four arms of said bridge, a controlled device in the crosswire of the bridge, and a source of current supply connected to the two ends of the bridge, the said radio-electr0-sensitive elements being arranged in pairs and the pairs being associated in such manner that increase or decrease of illumination of the radio-electroe ly- 'sensitive devices of such pairs afi'eets such devices of each pair similarly, and that in crease of illumination of one pair and corresponding decrease of illumination of the other pair affect the controlled element simi- .7 In telegraphy, a radio-electric relay i- .4 comprising one or more radio-electrosens1- tii e elements and a receiving instrument controlled thereby, and aninductive shunt around the receiving instrument adjusted to compensate for the inertia of the radio-elect-ro-sensitive element or elements. 1

12. In telegraphic apparatus of the kin referred to, the combination of a plurality of selenium cells arranged in separate branch circuits each connected with a generator, a receiving instrument also connected to said cells, means for projecting abroad beam of light upon such cells and for moving such beam over the surfaces of such cells in such manner, that as the illumination of one cell is decreased the illumination of another cell. is increased, the connections being such that the potentials'of the batteries of said selenium cells are normally opposed one to the other and balance each other when the illumination of the cells is approximately equal, and that increase of illumination of one cell and decrease of illumination of the V opposing'c'ell cooperate to produce operat-ion of the said'receiving instrument, and signal controlled means responsive to a telegraphic code of signals composed of electrical impulses of the same and revel d polarity and adapted to vary the degree of illumination of said cells.

13. In telegraphic apparatus of the kind referred to, a \Vheatstone bridge and selenium cells in the arms of such bridge, in combination with a. generator connected to the ends of such bridge and a receiving instr .nent contained in the cross wire of the bri e, and inductive resistance also in said cro wire and in shunt with respect to said receivino' instrument.

14-. The herein described method of transmitting, receiving and amplifying telegraphic signals, which consists in transmitrents of the opposite "polarity for anotherclass of signals of the telegraphic code, cans 1o ing the signals so transmitted to vary: the degree of illumination of cooperating radio-. electro-sensitive elements in electric circuits electrically ,so connected with the receiving instrument that increase of illumination of one such element and decrease of illumination of the other element have a cumulative efliect in reproduc-in and amplifying signals of the same po arity, said cooperatin radio-electro-sensitive elements being eac illumined to an intermediate and 'substam tial degree when no signals are being transmitted, signals of one polarity causing decrease of illumination of one element and increase of illumination of its cooperating element, ands'ignals of the opposite polarity causing increase of illumination of the ele' ment first referred to and decrease of illu1nination of its cooperating element, and da s-- ing the resultin current fluctuations in the circuits. of sai cooperating radio-electro: sensitive elements to operate electrical signalling meansy a 15. The herein "described methqd jo f receiving and amplifying telegraphic signals,v which consists in receiving signals a-;m mitted through an electric circuit by currents of one polarity for one class of signals, of the telegraphic code, and by currents the opposite. polarity; for another class signals of the telegraphic code, causing the sig: nals'to vary the degreetof illumination ,of cooperating radio-electro-sensitive elements in electric circuits so connected electrically with the receivingins trument that} increase of illumination of one such element and decrease of illumination of the other element have a cumulative effect in reproducing and amplifying signals of the'same polarity, said cooperating elements beiugieach illumincd to an intermediate al id substantial degree when no signals are being transmitted, signals of one polarity causing d crease of illumination of one element and in-v crease of illun'iination of its cooperating ch ment, and signals of the opposite polarity causing increase of illumination n tlurele ment first referred to and decrease of illui mination of its cooperating element -uand causing the resulting current fluctuations 'in I20 the-circuits of said cooperating radio-'eIectro-sensitive elements, to operate electrical, signaling means. i

16. In telegraphy, ajselenium signal am-, plilying apparatus embodying a 'n'ixnaryrel eeiving instrument and a secondary receiyi ng instrunient, an 'inductive shunt connected,

secondary receiving instrument. v.

17. In telegraphy, a selenium signal 25. An epparatusrlorreceiving and ampli amplifying apparatus embodying a primary tying i telegrnphic Signals comprising, in. receiying instrument, a secondary receiving combination, itradioelectro-sensitiVe device instrument, and an inductive shunt connect normally pen-daily(illuminated, a controlled edaround one of said instruments. elemennn circuit connecting said control'led '70 18.'In telegrephy, a selenium signal umelement and radio-electr e-sensitive devi (z plify'mg apparatus embodying a primary reand including a battery, another circuitnlo ceiv ngm'strument a, secondary receiving inincluding theradio-e1echo-sensitive element strunient'andin-inductiveehunt connected and battery and] containing-afhsitte'ry tr- Y 1 around theflpigil neceiiring instrument. f ranged to oppose with its .potentigilfthe fro-Q75, .19. In 'i. ,ii Selenium signal :nntential of the first mentioned buttery with f plif'ying mbodying a, primary rereference to the controlled element, 'un d a lso cei'v ng iuetru m including resistanceto balance theresistance n a econdary receiving instrument'yandfi ii inductivelshunt connected of the radio-eleetro-sensitive device, signal iiroundthe s epondary receiving instrument, controlled meansadnpted to vary'th degree: 80 I 20. -In1telegraphy, a, selenium signal n-inoi illuminetion-ofthe radimelecttrdsensitive. plifyingapparatusembodying a primary redevice and en inductive shunt connedted, c'eiving" instrument, n secondary receiving around thecontrolled eleinentr' if v instrument, an inductive shunt coi inected in Lle graphie apparatus of the kind aroux'id one of said instruments and n min" red to, reeeivinginstmment, andtwo 8.

inductive--resistancesin series; with Enid in branch circuits conneeted thereto one such duotive shunt. v eireuit containing a normally pa-i v 21, In telegraphy,-eseieniuin signei en'r iilini iinate'd selenium cell and ii -gene plifying apparatus embodying it primeryretiiei'f'hrunelr,eircuit containing ceiving instrument, secondary receivn tor o 'n Qthe firstment-ioned 9 0 0 instru'n'ient, an inductive shunt connected. eretor, and 2 n; idiniz resistance It around one of said instruments-end an ad: mail? enema t ,e reei-stanceofthe selenium j ustahle non-inductive resistance in cell, signal, eentrolled means responsive with said inductive shunt. teiegmphic cede composed of electrical 22. Tu telegraphy, 21 radio-electro signal H tee the snn'ieland reversed polarity amplifying apparatus embodying a primary l adapted to vary the degree of illuminar receiving instrument and a secondary re-- of cell, i l ceiving. instrument, an inzlnctiveshun'z con 2 in telegraphic apparatus of the kind nectod around the primary receiving instrnref rred tone receiving instrument, and two i 35 ment and i111 inductive shunt connected humeh circnite connected thereto, one sucharound the secondary receiving; instrument. n "inch circuit oontnining a normally par- 21- In. telegraphy, n radio-electro tinlly illuminated selenium cell .and'a gen- 'mnplifying apparatus emhodying; ereter, the other branch circuit containing a receiving instrument, a secoiulery o; gesing the first. mentioned gen- 40 instrument. an inductive Sl'ELaB't-q and. a nonenter and. also including resistance to norinductive resistance in series 'tlwrewith conmaiiy hnlunce the resistance of the selenium necled around the primary receiving inst; ieell, end, an inductive ehunt connected ment,- and an inductive shunt e215 non inaround the receiving ingtF-ument. ductive resistance in series the 28. in telegraph a receiving iuetrument,. 45 nected around the arm-Mada:y-reeea, circuit including at source of electrical strument. energy tor controlling the operation of the 24. An apparatus for receivingnmliuupli-' receiving ineiirument, radio-electro-sensitive tying telegraphic 'sig'nnis comprising in n'iene'u; included in Sr1l(l=( lI(-fl1lt, means for combination, u rmlio-elecnoseueitire device inn n2 liroud hemn of light upon the 50 normally partially illuminated a controlled metro-sensitive means for i normally element- :1 circuit connecting Enid controlled element and miiio-elei:tro-eensitire dev' ie to imrn'iull7 maintainthe radio-electro-sensL and including a. battery, another viinnit also tiw immineat is. proper rorlring resistance, including the. radio-ciectrosen Eve element and men 9; associated "with will cir uit for 55 and battery mid containing a battery :irnormz'ally lmlnnoing the e'flect of the current ranged to oppose with its potential. ti: 90- of said Cllffdll; on the Y'BCGlV-iflfl mstrumeng 4 tenti nl of the first mentioned liutl; with and an inductive shunt armmd t'he IEGGJYHIQ reference to the controlled element, and valso instmment; including resistance to haiance the resist-nice An :ip 'ieratus for receiving and ampli- 60 of the rzidiri-clectro-seus-itire.device, end i-ying telegrn 'alilc eigz'nals comprising, no] controlled means responsive to it tclecomiunntion, a selenium oell akzahle e rcuit graphic code con'i 'mseil of electrical inuiulsies 'mal y deenergized, a period of light norof the same and, reversed 'prilarity and iminntingg' n Slll'lSliLlllllLl portion of adapted to Vary the degree ofiliuminntion of the sell a grailvenometcr controlled by the 66 the radio-electro-sensitive device, cable circuit and embodying a reflector ar ranged to be oscillated through the opera tlon of the galvanometer andadapted to re fleet said pencil of light variably across the j a controlled element council of the selenium cell. 3 V 30. An apparatus forreceiving'and amplisurface of the seleniumcell, the .rest or zero position of said reflector,when-the cable circuit is normally deenergized, corresponding to a condition of partial and substantial illu mination of said cell by the li ht pencil, and

as by the circuit tying telegraphic 's1gnals-;,-compr1sing, in

combination, a selenium cell, a cable clrcuit normally 'deenergized, a pencil of light normally illuminating a substantial portion of the 'icell, a. galvanometer controlled by the cable circuit and embodying a reflector arranged to be oscillated through the opera tion of the gal'vanom'eter and adapted to reflect said: ncil of light-"variably across the surface of t he selenium cell, the .rest or zero position of said reflector, when the cable-circuit is normally deenergized, corresponding to a Condition of partial and substantial illumination of said cell by the light pencil, a controlled element controlled by the circuit ampliiying apparatus em receivlng instrument, a secondary rece ving of the selenium well, the movements of the pencil of light to one side of the zero position causlng the controlled element to indicate dots, while movements of said light pencil to the other side of the zero position cause said controlled element to indicate dashes, of a telegraphic code.

"31,. In telegraphy, a li ht-sensitivesignal ying a primary ii1stru1nent, and an inductive shunt around one of said instruments. v

32. In telegrsphy, a radio-electro-signal amplifying apparatus iembodying a primary receiving instrument responsive to a code of telegraphic signals composed of electrical impulses of the same and reversed polarity,

THOMASBULLITT DIXON. 

